Hard-partying photographer and artist Peter Beard — the 76-year-old former Studio 54 fixture who’s married to his agent, Nejma Beard — was seen kissing, hugging and frantically fondling a brunette beauty who wasn’t his wife.

We previously reported Beard conducted a sexy shoot with model Ingrid Levin in “a latex corset with lace trim” at a suite in the Sanctuary Hotel in Midtown last year. On Monday, the artist and Levin were back at the hotel for dinner when things got steamy — in front of her son.

A billboard with Ingrid Levin’s campaign

Spies said Levin, who’s appeared in a black bikini on billboards for Fontaine­bleau Miami Beach, met Beard at about 8 p.m. with Levin’s adult son. The trio dined at the hotel’s Haven Rooftop on a menu specially prepared by new restaurant Tender — but Beard had only Levin in mind as his appetizer.

“Ingrid’s son was beside her, but Peter still made it into a hot-and-heavy date,” a spy said. “He was hugging and squeezing and kissing her. They should have just checked into a room.”

Photos snapped by a guest show Beard smooching Levin with his hands all over her.

The source added Beard then squired Levin to a “secluded couch,” where he was “squeezing” her buttocks and breast outside her shirt, and had a hand creeping down her pants.

“His hands knew no bounds,” said a shocked spy.

The pair then went back to their table and left at about 12:30 a.m. Spies said Beard racked up a $450 tab but didn’t leave a tip. His mind must have been elsewhere.

Beard is known for photographing African wildlife as well as Mick Jagger, David Bowie and other stars. He suffered a stroke last year (which clearly hasn’t slowed him down).

Beard’s wife and spokeswoman Nejma insisted: “Peter had [dinner] at Nobu . . . he was invited to watch a Rangers game at a place called Sanctuary. The woman named Ingrid works at a club called Sapphire, she is not a model. It was not his dinner tab. Quite a spin, perhaps they need a better p.r. agent.”

But a staffer at Sapphire told us Ingrid doesn’t work there and “I’ve never heard of her.”